2 ways i would go about this:
one, you can get MyMobiler app which allows you to use/control you vouge from your pc with your keyboard and mouse and easily select all of your messages and hit the delete on your pocket pc. you can downloaded it here:
http://www.mymobiler.com/
or
second, you can install a small utility (reg edits actually) to your Vouge which will add 2 useful (and dangerous) "delete all" and "mark all as read" in the menu when using pocket outlook. (name is: InboxMenuExtensibility)
I removed my cab Maker and cant find a good program to work well so...
UPDATE: OK we are going to use the manual way..first, download the zip file attached. there will be 3 files in the zip. extract the zip and copy to your storage card. TaskMgr3.1.cab (install it of you do not have a registry editor):
copy the "InboxMenuExtensibility.dll" to your \windows folder
if using taskMgr, then start the program...click menu->tab options->Select Tab->regedit
then click on the bottom-left coner icon (looks like a thunder flash)->select import...
Then browse to where you saved extracted zip. select the reg file (long string of numbers and letters).
then soft-reset your device..that should do it.